Question: At what point in time did Birmingham have a population of 1123000?
Paraphrase: When did Birmingham's population reach 1123000?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q2256 p:P1082 ?s . ?s ps:P1082 ?x filter(contains(?x , '1123000')) . ?s pq:P585 ?value}